Mac Loc: Pittsburgh, Philadelphia now Hernando Co. Fl.

Even if lens manufacturers weren't thinking of human eye vision initially, it probably didn't take them long to notice distortion and/or lack of distortion at various focal lengths.
But they probably were aware of human eye vision in making their camera lenses. Most, if not all, early camera lens makers were microscope, or telescope, or eye glasses makers before they got involved with camera lenses.

JohnSwanda Loc: San Francisco

But where does peripheral vision begin? I feel like the human eye sees a LOT more than the 50mm lens sees.

JPL

I think I must try to do that. First, if I put a camera with a 27 mm lens on my chest and try to let my eye (I am one eyed bastard) be on vertical level with the front of the lens I always see a bit wider than the picture I get from the camera with that lens.

Another thing is that reading material on the internet about the human eye it usually comes down to 17-22 mm lens equiv. or wider for one eye but most of us have 2 eyes and see wider than that. But there is a catch, the eyes have denser "pixels" in the center with colors and everything while around the center you have fewer pixels and mosty black and white. People try to fix this with the idea of 50 mm lenses being normal because this colored and dense part of the eye "sensor" is close to 43 mm equiv. But little of this was known when 50 mm became the normal lens and like I said most humans see with 2 eyes making 2x43 mm much wider than a normal 50 mm lens. And when this kind of comparison is done it would be fair to keep in mind that the 50 mm camera lens also has vignetting and softness towards the edges so it is not logical to compare the whole lens to the sharp part of the eye. So I think there must be other reasons and just want to figure it out. I have never seen anything about that the designers of the first 50 mm lenses trying to match the human eye in any way so I just want to get to the bottom of this once and for all

http://www.cambridgeincolour.com/tutorials/cameras-vs-human-eye.htm
https://petapixel.com/2012/11/17/the-camera-versus-the-human-eye/
https://en.wikipedia.org/wiki/Human_eye

PixelStan77 Loc: Vermont/Chicago

IMHO
50mm isn't really "standard" on cropped sensor cameras. It's just popular because those lenses are cheap and take good photos. This is partly because the camera makers perfected these lenses over many years, and partly because that focal length makes for a simple lens. But be careful, on your camera 50mm is quite zoomed in.

mas24 Loc: Southern CA

My father's film camera, the Minolta SRT-101 from the 1970s, had a 50mm fixed lens. I had been told by photographers later, that was a lens that the eyes see. A 43mm later became the norm. But, I suppose it was not practical to make a 43mm lens. There are manufacturers who makes or made a 43mm lens. But, I have never seen one.

CPR Loc: Nature Coast of Florida

In the early days, think Nikon "F" just replacing my Speed Graphic 4X5, the 50mm lens gave a normal perspective to shots taken with the 35mm camera. I used the 50mm for newspaper shots and the 85mm was used for portraits or people up close shots.

Ghery Loc: Olympia, WA

And my SRT-102 (got it in 1975) came with the 50 mm lens as standard, as well. I shot a bunch of Kodachrome slides using that lens. I have a couple other lenses in the bag for that camera, as well, but the 50 mm got the most use (by far).

dennis2146 Loc: Eastern Idaho

My belief is that lens is what the majority of SLR’s came equipped with. Consumers bought them and generally that is the lens that stayed on the camera from then on. For those who really liked photography there were other lenses to be purchased.

Dennis

bobmcculloch Loc: NYC, NY

The diagonal of the 35mm frame is approximately 50mm, the original 35mm cameras were designed to produce 5x7 prints displayed on walls and viewed at more than arms length, at least as I remember reading half a lifetime ago, I probably still have the book someplace in the attic, at one point I read through The Life Library of Photography and the Encyclopedia of Photography, that was before the internet ate up all my time, Bob.

Rich1939 Loc: Pike County Penna.

I guess I'm an 'old timer' and I never owned a 50mm until recently. The lens that was on my camera(s) for every day use was a 35mm. Cropping the image to what was considered then to be the normal ratio of 4:5 helped reduce any apparent distortion. Food for thought; many have suggested that a normal lens for a given format should approximate the diagonal of the negative. The diagonal of a 35mm negative (cropped to 4:5 ratio) is approximately 38mm. If you never intend to use the entire negative shouldn't your standard then be based on what your used size is? Today's accepted normal ratio seems to be 4:6. We can blame big Yellow (aka Kodak) for that. When general photography moved to 35mm and try as they might Kodak could not get the majority of users to go to Kodak preferred formats, they accepted reality and decided to make more money from it by offering 4x6 'jumbo' prints instead of the former 3.5 x 5. They also offered 8x12 prints as an alternative to the standard 8x10. Of course these larger sizes cost more. Personally I think the older 4:5 ratio produces a more balanced look but, that's what I grew up with. Those who 'came up' with the 4:6 ratio will opine differently.

bobmcculloch Loc: NYC, NY

BTW, a 135mm was 'normal' on a 4x5, Bob.

Toby

I won't argue the technical details but just suggest a simple test. Put a zoom lens on your camera and then focus on something. As you move thru the zoom range stop when you see the right eye image blend with the left eye image. What's the lens setting?

Rich1939 Loc: Pike County Penna.

I would love to see responses to this!

JPL

Thanks for the suggestion, but I will not do that. As I have already mentioned here I am one eyed so this will not work for me

BebuLamar

On my nikon Df it's about 80mm. But that changes with camera. With older camera like the Pentax KX or Minolta XK it's about 58mm. This does not define the normal lens because it's depend on viewfinder magnification and the newer cameras tend to have lower magnification than older ones.
If viewfinder is specified as 1X magnification then the 50mm the image size are the same thru the viewfinder as well with naked eye.